④ Verification of current transformer (CT) a. Dynamic stability verification The dynamic stability current of the selected switchgear is 80kA, which is greater than the short-circuit thermal thermal stability current of the GIS substation 110KV system 20.08kA, so it meets the thermal stability requirements. b. Thermal stability verification The thermal stability current of the selected switchgear is 32kA, which is greater than the thermal stability current of the GIS substation 110kV system short circuit 20.08kA, so it meets the thermal stability requirements. ⑤. Busbar verification a. Ue = 1 10kV, I = 1250A> GIS substation maximum long-term working current Igmax = 262.432A b.110kV side busbar three-phase short-circuit steady-state current = 20.08 kA rated heat of the selected switchgear circuit breaker The stable current is 31.5 kA so it meets the requirements. Voltage transformer (PT), the arrester need not test its thermal stability and dynamic stability, so here without making correction experience. Selection of equipment (1). Rated voltage: Ue = 35kV (2). Rated current: le> Maximum long-term working current Igmax of GIS substation, ie (3). According to the above analysis, choose the KYN7-40.5 type armor of Xi’an High Voltage Switch Factory Removable indoor AC metal enclosed switchgear, the relevant parameters are shown in Table 4-2.